大涡模拟壁湍流雷诺剪切应力
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最近验证算例，LES模拟壁面湍流，与文献结果对比，雷诺应力偏离较大；
采用边界层网格，第一层网格尺寸满足y+=1，入口出口cyclicAMI周期边界条件，因为是不可压缩，所以fvoption直接给出的是Ubar，大概算了80个周期后，做时均，平均速度与文献结果差不多，但关于速度脉动的湍动能和雷诺应力完全不一致，这个问题一直也没有解决，求教高手解答；
注：关于雷诺剪切应力我是通过uprime2mean_xy+turbulencefieldsR_xy得到的，模拟输出的turbulencefieldsR相比uprime2mean来说很小； -
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可以出个图看看差别有多大
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LES那面Van Driest dampling用的比较多，从文献来看可以大大改善壁面附近的预测
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@东岳 老师，目前在试算，所以我用的是一套二维网格，亚格子模型为WALE
simulationType LES; LES { LESModel WALE; turbulence on; printCoeffs on; delta cubeRootVol ; cubeRootVolCoeffs { deltaCoeff 1; } PrandtlCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } Cdelta 0.158; } vanDriestCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } Aplus 26; Cdelta 0.158; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } }您说的van driest damping是vanDriestCoeffs里的设置吗？
上面的图是平均速度，实验数据为黑线，下方的正弦曲线是底部边界；5-30s我开始认为湍流没有完全发展，所以一直算到200s，又对100-200s取时均，定性上看，两个时间段的平均速度变化差不多；
雷诺应力的图被我删掉了，有关于湍动能的结果，实验数据为黑线，这个就完全不一致，而且不同时间段的湍动能时均值也不一致；
以下是我的设置：FoamFile { version 2.0; format ascii; class volScalarField; object nut; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 -1 0 0 0 0]; internalField uniform 0; boundaryField { INLET { type cyclicAMI; } OUTLET { type cyclicAMI; } BOTTOMWALL { type nutUSpaldingWallFunction; value uniform 0; } ATMOSPHERE { type nutUSpaldingWallFunction; value uniform 0; } frontAndBackPlanes { type empty; } }FoamFile { version 2.0; format ascii; class volScalarField; object p; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 2 -2 0 0 0 0]; internalField uniform 0; boundaryField { INLET { type cyclicAMI; } OUTLET { type cyclicAMI; } BOTTOMWALL { type zeroGradient; } ATMOSPHERE { type zeroGradient; //p0 uniform 0; } frontAndBackPlanes { type empty; } }FoamFile { version 2.0; format ascii; class volVectorField; object U; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // dimensions [0 1 -1 0 0 0 0]; internalField uniform (0 0 0); boundaryField { INLET { type cyclicAMI; } OUTLET { type cyclicAMI; } ATMOSPHERE { type noSlip; //value uniform (0 0 0); } BOTTOMWALL { type noSlip; } frontAndBackPlanes { type empty; } }FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object fvOptions; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // momentumSource { type meanVelocityForce; selectionMode all; fields (U); Ubar (0.08 0 0); }FoamFile { version 2.0; format ascii; class dictionary; location "system"; object fvSchemes; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // ddtSchemes { default Euler; } gradSchemes { default Gauss linear; } divSchemes { default none; div(phi,U) bounded Gauss linearUpwind grad(U); div(phi,k) bounded Gauss limitedLinear 1; div(phi,epsilon) bounded Gauss limitedLinear 1; div(phi,omega) bounded Gauss limitedLinear 1; div(phi,v2) bounded Gauss limitedLinear 1; div((nuEff*dev2(T(grad(U))))) Gauss linear; div(nonlinearStress) Gauss linear; } laplacianSchemes { default Gauss linear corrected; } interpolationSchemes { default linear; } snGradSchemes { default corrected; } wallDist { method meshWave; }FoamFile { version 2.0; format ascii; class dictionary; location "system"; object fvSolution; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // solvers { p { solver PCG; preconditioner DIC; tolerance 1e-06 relTol 0.05; } pFinal { $p; relTol 0; }; "(U|k|B|nuTilda)" { solver smoothSolver; smoother GaussSeidel; tolerance 1e-05; relTol 0; } } PISO { nCorrectors 2; nNonOrthogonalCorrectors 0; pRefCell 0; pRefValue 0; }希望得到老师的回复，谢谢。
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@ewz 把你的divSchemes里面的bounded去掉，然后时间精度换backward试试。还有就是nut的边界条件nutUSpaldingWallFunction，这个可以换别的试试，具体哪个更好也说不清。
另外，你模拟的是什么？挺有意思的，要发SCI么，可以考虑下 http://www.cfd-china.com/topic/1716/cfd验证算例支持计划
黑线是实验数据，红线是什么？
vanDriest这样用：
simulationType LES; LES { LESModel WALE; turbulence on; printCoeffs on; delta vanDriest;// cubeRootVolCoeffs { deltaCoeff 1; } PrandtlCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } Cdelta 0.158; } vanDriestCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } Aplus 26; Cdelta 0.158; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } }CFD课程 改成线上了 http://dyfluid.com/class.html
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@东岳 好的，谢谢老师！我调试参数再算一下；
我模拟的是wave surface壁面湍流，因为目前是验证LES的阶段，就找了一篇关于实验的文献；
红线数据是三维计算域的实验结果； -
@李东岳 WALE不需要vanDriest吧？
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Referenced by C coolhhh
